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THE 



PHILOSOPHICAL MAGAZINE 

 AND JOURNAL: 



COMPRBHBNDIN6 



THE VARIOUS BRANCHES OF SCIENCE, 



THE LIBERAL AND FINE ARTS, 



GEOLOGY, 



AGRICULTURE, 



MANUFACTURES AND COMMERCE. 



NUMBER CCLXVin. 

 For AUGUST 18r20. 



BY ALEXANDER TILLOCH, 



M.a.I.A. M.O.S. M.R.A.8. MUNICH, F.S.A. EDIN. AND PERTH, 

 M.S.E.I.N. OF FRANCE, &C. &C. &C. 



LONDON: 



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